JP7490067B2 - Method and device for power conservation in wireless sidelink communications - Patents.com - Google Patents

Description

This disclosure relates generally to wireless communications, and specifically to the allocation and configuration of sidelink communication and control resources for power conservation.

User equipment in a wireless network may communicate data with each other directly over sidelink communication channels without the data being relayed by any radio access network node. Some application scenarios of sidelink communication, such as those involving vehicular wireless network devices, may have communication requirements that are more stringent and unpredictable compared to other conventional applications involving UE-UE sidelink communication. It becomes important to provide resource allocation and provisioning mechanisms that enable low-power and efficient use of both sidelink communication resources and control resources.

The present disclosure is directed to methods, systems, and devices related to wireless communications, and more specifically, to power conservation in sidelink communications between communication terminals.

In one embodiment, a method for wireless sidelink communication is disclosed. The method includes receiving, by a user equipment (UE), a plurality of radio resource configurations corresponding to a plurality of sidelink resource pools for the sidelink communication, and selecting, by the UE, a sidelink resource pool from the plurality of sidelink resource pools for the sidelink communication based on a traffic type of the sidelink communication. The traffic type is indicated by at least one of a destination identification, a cast type, or quality of service (QoS) information of the sidelink communication.

In another embodiment, a method for wireless sidelink communication is disclosed. The method includes receiving, by a UE, a radio resource configuration for a sidelink resource pool; and selecting, by the UE, a time division from N time divisions of the sidelink resource pool for the sidelink communication based on a traffic type of the sidelink communication, where the number N is a positive integer, and the traffic type is indicated by at least one of a destination identification, a cast type, or QoS information of the sidelink communication.

In another embodiment, a method for wireless sidelink communication is disclosed. The method includes receiving, by a UE, a radio resource configuration containing a sidelink resource pool for sidelink communication comprising a first set of sidelink time and frequency resources and a sidelink control resource configuration for indicating a second set of sidelink resources for transmission of sidelink control information. The method further includes transmitting, by the UE, the sidelink communication via a first sidelink resource of the first set of sidelink time and frequency resources, and transmitting, by the UE prior to transmitting the sidelink communication, sidelink control information via a second sidelink resource of the second set of sidelink resources for indicating to the receiving UE whether to monitor the sidelink resource pool for a configured period following reception of the sidelink control information.

In another embodiment, a method for wireless sidelink communication is further disclosed. The method includes receiving, by the UE, a radio resource configuration containing a sidelink resource pool for sidelink communication comprising a first set of sidelink time and frequency resources and a sidelink control resource configuration for indicating a second set of sidelink resources for transmission of sidelink control information. The method further includes monitoring, by the UE, the second set of sidelink resources for sidelink control information, providing the UE with an indication to monitor the sidelink resource pool for receiving sidelink communication for a configured period following reception of the sidelink control information, and monitoring, by the UE, the sidelink resource pool for receiving sidelink communication for the configured period after receiving the sidelink control information with the indication.

Various devices are also disclosed. Each of these devices includes a processor and a memory, the processor configured to read computer code from the memory and implement any one of the methods described above.

A computer-readable medium is further disclosed. Such a computer-readable medium includes instructions that, when executed by a computer, cause the computer to perform any one of the methods described above.

These and other aspects and their implementations are described in more detail in the drawings, description, and claims below.
For example, the present application provides the following:
(Item 1)
1. A method for wireless sidelink communications, comprising:
receiving, by a user equipment (UE), a plurality of radio resource configurations corresponding to a plurality of sidelink resource pools for sidelink communication;
selecting, by the UE, a sidelink resource pool from the plurality of sidelink resource pools for sidelink communication based on a traffic type of the sidelink communication.
Including,
The method of claim 1, wherein the traffic type is indicated by at least one of a destination identification, a cast type, or quality of service (QoS) information of the sidelink communication.
(Item 2)
2. The method of claim 1, wherein the plurality of radio resource configurations comprise resource bitmaps, each corresponding to one of the plurality of sidelink resource pools.
(Item 3)
1. A method for wireless sidelink communications, comprising:
receiving, by the UE, a radio resource configuration for a sidelink resource pool;
selecting, by the UE, a time division from N time divisions of the sidelink resource pool for sidelink communication based on a traffic type of the sidelink communication.
Including,
wherein N is a positive integer and the traffic type is indicated by at least one of a destination identification, a cast type, or QoS information of the sidelink communication.
(Item 4)
The radio resource configuration is
a first information element for identifying sidelink resources allocated to the radio resource configuration; and
a second information element including a positive integer equal to N;
4. The method of claim 3, comprising:
(Item 5)
The radio resource configuration is
a first information element including N time bitmaps for identifying N time divisions of the sidelink resource pool;
a second information element for indicating frequency allocation information for all N time divisions of the sidelink resource pool;
4. The method of claim 3, comprising:
(Item 6)
The or each of the plurality of radio resource configurations
A radio resource configuration identifier;
a power saving indicator, the power saving indicator being for indicating that a corresponding sidelink resource pool is available for use by the UE for sidelink communication in a power saving mode; or
A traffic type indicator for indicating one or more traffic types.
6. The method according to any one of items 1 to 5, further comprising at least one of:
(Item 7)
6. The method according to claim 1, wherein the or each of the radio resource configurations comprises one or more sidelink control resource configurations for indicating a set of sidelink control resources for transmitting one or more sidelink control information.
(Item 8)
The method further comprises transmitting, by the UE, sidelink control information via one of the set of sidelink control resources prior to transmitting the sidelink communication via the selected sidelink resource pool or a selected time division of the sidelink resource pool, and indicating to a receiving UE whether to monitor the sidelink resource pool, a selected time division of the sidelink resource pool, the plurality of sidelink resource pools, or the selected sidelink resource pool, during a configured period following reception of the sidelink control information.
8. The method of claim 7, further comprising:
(Item 9)
The method further comprises, prior to monitoring, by the UE, the selected sidelink resource pool or a selected time division of the sidelink resource pool for receiving the sidelink communication, monitoring, by the UE, one or more sidelink control information via the set of sidelink control resources, and receiving, to a receiving UE, sidelink control information indicating whether to monitor the sidelink resource pool, a selected time division of the sidelink resource pool, the plurality of sidelink resource pools, or the selected sidelink resource pool, during a configured time period following reception of the sidelink control information.
8. The method of claim 7, further comprising:
(Item 10)
9. The method according to claim 8, wherein each sidelink resource pool comprises one or more sidelink on durations.
(Item 11)
9. The method according to claim 8, wherein the one or more sidelink control resource configurations correspond to one or more time points corresponding to the one or more sidelink control information, respectively.
(Item 12)
the sidelink control information is transmitted at one or more of the time points;
the configured time period corresponds to a time between a point in time and a next point in time within the one or more points in time;
Item 12. The method according to item 11.
(Item 13)
9. The method according to claim 8, wherein the sidelink control information includes a wake-up indicator to indicate to the receiving UE whether to monitor the sidelink resource pool, a selected time division of the sidelink resource pool, the multiple sidelink resource pools, or the selected sidelink resource pool, during a configured period following reception of the sidelink control information.
(Item 14)
14. The method of claim 13, wherein the sidelink control information comprises a sidelink control message including the wake-up indicator.
(Item 15)
14. The method of claim 13, wherein the one or more sidelink control information are associated with traffic of a sidelink transmission, and correspondingly, the sidelink control information transmitted by the UE further comprises traffic type information associated with a traffic type of the sidelink communication.
(Item 16)
1. A method for wireless sidelink communications, comprising:
By the UE,
a sidelink resource pool for sidelink communication comprising a first set of sidelink time and frequency resources;
a sidelink control resource configuration for indicating a second set of sidelink resources for transmission of sidelink control information; and
receiving a radio resource configuration comprising:
transmitting, by the UE, sidelink communication via first sidelink resources of the first set of sidelink time and frequency resources;
transmitting, by the UE, prior to transmitting the sidelink communication, sidelink control information via a second sidelink resource of the second set of sidelink resources to indicate to a receiving UE whether to monitor the sidelink resource pool during a configured period following reception of the sidelink control information.
A method comprising:
(Item 17)
1. A method for wireless sidelink communications, comprising:
By the UE,
a sidelink resource pool for sidelink communication comprising a first set of sidelink time and frequency resources;
a sidelink control resource configuration for indicating a second set of sidelink resources for transmission of sidelink control information; and
receiving a radio resource configuration comprising:
monitoring, by the UE, the second set of sidelink resources for sidelink control information providing an indication to the UE to monitor the sidelink resource pool for receiving the sidelink communication during a configured period following reception of the sidelink control information;
monitoring, by the UE, the sidelink resource pool for receiving the sidelink communication for the configured period of time after receiving the sidelink control information with the indication.
A method comprising:
(Item 18)
The radio resource configuration is
an identifier for said sidelink resource pool for sidelink communication; or
an indicator for indicating that the sidelink resource pool is available for use by a UE in a power saving mode.
18. The method of any one of claims 16 or 17, further comprising at least one of:
(Item 19)
the sidelink control information is transmitted at one or more of the time points;
the configured period corresponds to a time between a first point in time of a resource of the second set of sidelink resources for transmitting the sidelink control information and a second point in time for a next resource in the second set of sidelink resources.
18. The method according to any one of items 16 or 17.
(Item 20)
18. The method according to any one of items 1-5 or 16-17, wherein the UE receives the radio resource configuration or the plurality of radio resource configurations via pre-configuration.
(Item 21)
18. The method according to any one of items 1-5 or 16-17, wherein the UE receives the radio resource configuration or the multiple radio configurations from its serving cell.
(Item 22)
18. A method for establishing a sidelink connection for a first UE and a second UE based on a direct communication request message by the first UE, wherein a resource configuration for the direct communication request message by the first UE is according to any one of the methods described in items 1-5 or 16-17.
(Item 23)
23. The method according to claim 22, wherein the target user information in the direct communication request message is treated as the destination identification in any one of the methods according to claims 1-5 or 16-17.
(Item 24)
A device comprising a processor and a memory, the processor configured to read computer code from the memory and to implement the method according to any one of items 1-5 or 16-17.
(Item 25)
A computer-readable medium comprising instructions that, when executed by a computer, cause the computer to perform the method of any one of items 1-5 or 16-17.

FIG. 1 illustrates an exemplary diagram of a wireless communication network, in accordance with various embodiments.

FIG. 2 illustrates an example wireless data and control resource allocation and configuration scheme for sidelink communications.

FIG. 3 illustrates an example logic flow for information exchange between two user equipment for unicast sidelink configuration and communication.

FIG. 4 illustrates another example logic flow for information exchange between two user equipment for unicast sidelink configuration and communication.

FIG. 5 illustrates an example logic flow for information exchange between user equipment for groupcast sidelink configuration and communication.

FIG. 6 illustrates another example logic flow for information exchange between user equipment for groupcast sidelink configuration and communication.

FIG. 7 illustrates an example wireless data communication resource allocation and configuration scheme for broadcast sidelink communications.

FIG. 8 illustrates another example wireless data communication resource allocation and configuration scheme for broadcast sidelink communications.

FIG. 9 illustrates another example wireless data communication resource allocation and configuration scheme for broadcast sidelink communications.

DETAILED DESCRIPTION Techniques and examples of implementations and/or embodiments in the present disclosure can be used to improve performance in wireless communication systems. The term "exemplary" is used to mean "an example of" and does not imply an ideal or preferred example, implementation, or embodiment unless otherwise stated. Section headings are used in this disclosure to facilitate understanding and are not intended to limit the techniques disclosed in that section to only the corresponding section. However, it should be noted that implementations may be embodied in a variety of different forms, and thus, the scope of the present disclosure or claimed subject matter is not intended to be construed as being limited to any of the embodiments set forth below. Various implementations may be embodied as methods, devices, members, or systems. Thus, embodiments of the present disclosure may take the form of, for example, hardware, software, firmware, or any combination thereof.

Vehicle network refers to a network system for wireless communication and information exchange between vehicles, pedestrians, roadside equipment, the Internet, and other data networks through various communication protocols and data exchange standards. Vehicle network communication helps to improve road safety, increase traffic efficiency, provide broadband mobile data access and inter-network node data exchange. Vehicle network communication can be classified into various types as distinguished according to communication endpoints, including, but not limited to, vehicle-to-vehicle (V2V) communication, vehicle-to-infrastructure/vehicle-to-network (V2I/V2N) communication, and vehicle-to-pedestrian (V2P) communication. These types of communication are collectively referred to as vehicle-to-X (V2X) communication.

Vehicular networks may rely heavily on sidelink communications between terminal devices or user equipment (UE) in the network. Sidelink communications as used in this disclosure refers to direct wireless information exchange between UEs. For example, V2X communications may rely on direct sidelink data exchange from a source UE to a destination UE over the air interface without automatic forwarding by any radio base station. Such a communication mode has been studied and implemented within the 3rd Generation Partnership Project (3GPP). An exemplary V2X subsystem based on sidelink communications technology is illustrated as part of FIG. 1 and may be referred to, for example, as PC5-based V2X communications or V2X sidelink communications.

Application scenarios for V2X communications are becoming increasingly broad and diverse. Advanced V2X services and applications include, but are not limited to, vehicle platooning, extended sensors, semi-autonomous driving, fully autonomous driving, and remote driving. These applications and services require even higher network performance, including wider bandwidth, lower latency, and higher reliability. For example, these applications and services may require the underlying sidelink communication technology to support communication data packets of 50-12,000 bytes in size, message transmission rates of 2-50 messages per second, maximum end-to-end delays of 3-500 milliseconds, transmission reliability of 90%-99.999%, data transmission rates of 0.5-1,000 Mbps, and signal ranges of 50-1,000 meters, depending on the specific data services required for these applications.

Although it is possible for the various UEs described above to communicate between them using a sidelink, they may also be connected to a radio access network and, via the access network, to a core network. The radio access network and the core network may be involved in configuring and provisioning communication resources required for transmission/reception of data and control information for sidelink communication. An exemplary radio access network may be based on, for example, cellular 4G LTE or 5G NR technologies and/or formats. FIG. 1 shows an exemplary system diagram of a radio access communication network 100 including UEs 102, 124, and 126, and a radio access network node (WANN) 104. Each of the UEs 102, 124, and 126 may include, but are not limited to, a mobile phone, a smartphone, a tablet, a laptop computer, a vehicle-mounted communication device, a roadside communication device, a sensor device, a smart appliance (such as a television, a refrigerator, and an oven), or other device capable of wirelessly communicating via the network. The UEs may communicate with each other indirectly via the WANN 104 or directly via the sidelink. As shown in FIG. 1, UE 102 may include transceiver circuitry 106, e.g., coupled to antenna 108 to provide wireless communication with WANN 104 or with another UE, such as UE 124 or 126. Transceiver circuitry 106 may also be coupled to processor 110, which may also be coupled to memory 112 or other storage device. Memory 112 may store therein computer instructions or code that, when read and executed by processor 110, cause processor 110 to implement various ones of the methods for sidelink resource allocation/configuration and data transmission/reception described herein.

Similarly, WANN 104 may include base stations or other wireless network access points capable of wirelessly communicating with one or more UEs via the network. For example, WANN 104 may be implemented in the form of a 4G LTE base station, a 5G NR base station, a 5G central unit base station, or a 5G distributed unit base station. Each of these types of WANNs may be configured to perform a corresponding set of wireless network functions. WANN 104 may include transceiver circuitry 114 coupled to antennas 116, which may include antenna towers 118 in various forms to provide wireless communication with UEs 102, 124, and 126. Transceiver circuitry 114 may be coupled to one or more processors 120, which may further be coupled to memory 122 or other storage devices. Memory 122 may store therein instructions or code that, when read and executed by processor 120, cause processor 120 to implement various functions. These functions may include, for example, those related to the configuration and provisioning of wireless communication resources used for the exchange of data and control information in sidelink communications between UEs.

For simplicity and clarity, only one WANN and three UEs are shown in the wireless communication access network 100. It should be understood that one or more WANNs may be present in a wireless communication network, and each WANN may serve one or more UEs. Although the UEs 102, 124, and 126 in FIG. 1 are shown as being served within one serving cell, they may alternatively be served by different cells and/or not be served by any cell. Various embodiments of sidelink communications below are discussed in the context of a particular exemplary cellular wireless communication access network 100, although the underlying principles apply to other types of wireless communication networks.

The sidelink communications between the various UEs in FIG. 1 may support the coexistence of various distinct communication cast types, including unicast, groupcast (or multicast), and broadcast. In conventional techniques, UEs deployed in the access network 100 are required to perform comprehensive monitoring of a wide range of sidelink radio resources in either unicast, groupcast, or broadcast modes, which may incur a large amount of power consumption. Some power consumption may be at an unacceptably high level for some low-power UEs. To combat such issues, various implementations described in this disclosure provide methods, devices, and systems for configuring and provisioning wireless communication resources for carrying sidelink data and/or for carrying sidelink control information and enabling UEs to reduce their power consumption in monitoring and receiving unicast, groupcast, or broadcast sidelink data.

Radio communication resources for the transmission of either data or control information may generally be allocated in a time dimension and a carrier frequency dimension. Each of these dimensions may be allocated and provisioned according to its minimum allocation granularity. A sidelink resource allocation may be defined as a collection of time-frequency blocks. Sidelink data communication resources may be configured and allocated, for example, as one or more sidelink resource pools. Each sidelink resource pool may be associated with one resource configuration. For the purposes of this disclosure, the focus is on the time dimension of resource allocation. In particular, the time resources may be allocated at the granularity of a time slot of a given length of time. Alternatively, the time resources may be allocated at the symbol level.

One example of a resource pool allocated to a UE for sidelink data communications is illustrated as 200 in FIG. 2. Such a resource pool may be configured and allocated to a UE for either unicast, groupcast, or broadcast. The sidelink communications resources allocated within the resource pool are illustrated as various vertical bars arranged along a time axis 202, with their widths representing the time allocations and their height dimensions representing the allocations of carrier frequencies. Although the frequency allocations for each time are illustrated in FIG. 2 as being the same (as indicated by the same frequency ranges) within the resource pool, each of these resource bars may contain any suitable collection of any number of any carrier frequencies. Each of the bars may occupy one or more time slots or time symbols along the time axis 202. The time gaps between the bars indicate periods during which no time resources are allocated for sidelink data communications. For simplicity of the implementation description below, each of these bars will be referred to as a sidelink data communications resource.

Such a sidelink resource pool of FIG. 2 for a particular UE use in the step of transmitting or receiving sidelink data may be configured from the network side, e.g., the WANN of the serving cell for the UE. In particular, a control message corresponding to the sidelink resource configuration may be transmitted from the WANN to the UE. Alternatively, the sidelink resource pool may be pre-configured. In some other implementations, the UE may receive a sidelink communication resource configuration from another UE. A UE may be allocated with multiple sidelink resource pools, each defined by a corresponding sidelink resource configuration.

As an example, a sidelink resource pool 200 for a UE may be defined in a sidelink discontinuous reception (DRX) configuration transmitted to the UE. Such a resource pool 200 as configured by the DRX configuration may include sidelink resources in a repeating period called a sidelink resource period (SRP), as shown by 206 and 208 in FIG. 2. Periods 206 and 208 each represent a sidelink resource configuration cycle. Such a sidelink resource configuration may include one or more resource bitmaps that indicate the location of these allocated resources in the resource pool 200 in time and frequency for the configuration cycle, and then repeat periodically between SRPs.

The duration occupied by resources allocated for sidelink communication on the time axis 202 of FIG. 2 may be referred to as a sidelink on duration, as indicated by 210. The time gap between sidelink on durations may be referred to as a sidelink off duration, as indicated by 212. When attempting to receive sidelink data in either unicast, groupcast or broadcast state, the UE only needs to perform data monitoring for at most the sidelink on duration, thereby reducing data monitoring power consumption. If the UE is configured with a sidelink resource pool, the time slots or symbols contained within the sidelink resource pool constitute the sidelink on duration. Alternatively, if the UE is configured with a sidelink DRX configuration, in the DRX cycle, the DRX on duration represents the sidelink on duration. The sidelink on duration may be indicated by one or more time bitmaps.

Various exemplary embodiments described in more detail below relate to the configuration of resources for carrying sidelink control information and/or data information and some exemplary constructs of sidelink control information, which enable the UE to further reduce power consumption in sidelink communication.
First Exemplary Embodiment

In the various implementations of this embodiment described below, it is assumed that a first UE (UE1) and a second UE (UE2) have established a connection for sidelink communication, for example in unicast mode. UE1 represents a sidelink data transmitter and UE2 represents a corresponding sidelink data receiver. The implementations below are designed to allow UE2 to further reduce its power consumption when monitoring and receiving data from UE1.

In one implementation, UE1 and UE2 may first exchange capability information. Such capability information may include, but is not limited to, whether UE1 or UE2 supports a sidelink power saving function (SPSF). Once UE1 determines that UE2 is a P-UE or otherwise supports SPSF, or that the data to be transmitted by UE1 belongs to a data service with a destination identifier corresponding to a P-UE targeted service, UE2 may first transmit, for example, a DRX configuration of a sidelink resource pool to UE1, or alternatively, transmit a configuration for a limited time range of a sidelink resource pool to UE1. Prior to transmitting such a sidelink resource configuration to UE2, UE1 may obtain the configuration from the network side, for example, the WANN of its serving cell. In some other implementations, rather than transmitting a sidelink resource configuration from UE1 to UE2, UE2 may obtain such a configuration directly from its network side, for example, the WANN of its serving cell. Such a configuration may then be transmitted from UE2 to UE1 so that UE1 may determine sidelink communication resources for transmitting sidelink data to UE2. The sidelink resource configuration contains an allocation of sidelink resources as a sidelink resource pool, as indicated by 200 in FIG. 2.

Once UE2 receives the sidelink resource configuration, it then determines the sidelink on durations as shown in Fig. 2 for monitoring for sidelink data from UE1. In particular, it only needs to perform active monitoring within the sidelink on durations and changes to sleep during the sidelink off durations. It may for example monitor during all of the sidelink on durations labeled as 1-11 in Fig. 2. Since UE1 may not transmit sidelink data in all of these sidelink on durations, UE2 may further be controlled to actively monitor only during a subset of the sidelink on durations, further reducing monitoring power consumption. In some implementations, the time range that UE2 is required to monitor for sidelink data may be divided into several time divisions, such that UE2 may be controlled to monitor over several time divisions. To achieve that, corresponding sidelink wake-up control resources may be configured at the start of each time division. Sidelink wakeup control information or signals (referred to herein as either wakeup control information or wakeup control signals) may be carried on the sidelink wakeup control resources and transmitted to the UE to indicate to the UE whether the UE is required to monitor the sidelink on duration in subsequent time divisions (after a first time point corresponding to a sidelink wakeup control resource, until a second time point corresponding in time to the next wakeup control resource).

Such a scheme is shown in FIG. 2. In particular, arrows W1-W6 (labeled as 204) indicate the time location of sidelink wakeup control resources. As an example, they divide the sidelink communication resources 200 (bars) into three time divisions per SRP (e.g., SRP 206). The first time division includes sidelink on duration 1-3, while the second time division includes sidelink on duration 4-8 and the third time division includes sidelink on duration 9-12. Whether UE2 is required to monitor the sidelink on duration can be controlled between the time divisions.

One or more wake-up control resources 204 can be configured to indicate a time point (time slot or time symbol point) when UE2 is required to monitor the physical sidelink control channel (PSCCH) to receive wake-up control information or signaling. The wake-up control information or signaling indicates whether the UE should monitor the sidelink on duration during the time division following the wake-up control information/signal. The length of such a time division may be referred to as a configured period equal to the time length between the time point corresponding to the current wake-up control resource and the time point corresponding to the next wake-up control resource. For example, as shown in FIG. 2, if UE2 receives wake-up control information or signaling at time W1 indicating that UE2 needs to wake up to monitor for sidelink data, UE2 wakes up after W1 but before W2 and monitors sidelink on durations 1, 2, and 3 to monitor and receive sidelink data. For another example, if UE2 monitors for wake-up control information or signals in W2 and does not receive any wake-up control information or signals (or determines that the received wake-up control information or signals indicate that UE2 does not need to wake up), then UE2 wakes up after W2 and before W3 to receive sidelink data and does not need to monitor sidelink on durations 4, 5, 6, 7, and 8.

FIG. 3 illustrates an example logic flow 300 for information exchange between UE1 and UE2 according to the embodiment described above. As shown in FIG. 3, transmitting UE1 302 and receiving UE2 304 may establish a sidelink connection as shown at 306. They may further exchange sidelink capabilities as shown at 308 and described above. For power saving, a wake-up control resource configuration may be sent from UE1 to UE2 or from UE2 to UE1 as shown by 310. The exchange of the wake-up control resource configuration between UE1 and UE2 may be accomplished, for example, via a PC5-RRC (Radio Resource Control) channel and interface. The wake-up control resource configuration may be provided by the network side. For example, the network side of UE1 (e.g., the WANN of its serving cell) may provide such a wake-up control resource configuration to UE1, and UE1 may obtain the wake-up control resource configuration from the network side and then transmit the wake-up control resource configuration to UE2. Alternatively, the network side of UE2 (e.g., the WANN of its serving cell) may provide such a wake-up control resource configuration to UE2, and UE2 may obtain the wake-up control resource configuration from the network side and then transmit the wake-up control resource configuration to UE1. Either UE1 or UE2 may first transmit sidelink UE information to the network side to request the wake-up control resource configuration from the network side. Such UE information may include at least one of the various items in list 1 below.

The information elements in List 1 are used by the network side (WANN and/or some other network node in the core network) to determine sidelink control resource allocation and configuration, including, for example, information related to the traffic type of the sidelink communication. The traffic type information may include, for example, the destination identification (service type) of the sidelink communication for which the wake-up control resources need to be determined, the cast type (indicator of the cast type, such as unicast, groupcast, or broadcast), and quality of service (QoS) information. The QoS information may be represented, for example, by a QoS flow identification (QFI) and/or a QoS profile corresponding to the sidelink communication. Some of these information elements may be optional, while others may be mandatory, and the above list is provided only as an example.

Continuing with the logic flow of FIG. 3, when UE1 has a sidelink to transmit or its sidelink data buffer is not empty, as shown at 312, it first transmits wake-up control information or signal on a wake-up control resource (e.g., sidelink control time resource W1 in FIG. 2) preceding the sidelink resource, e.g., to transmit sidelink data (resource bar or sidelink on duration 1 in FIG. 2) to UE2 via the physical sidelink control channel (PSCCH), as shown at 314. Such signal is monitored by UE2, as shown at 316. UE2 receives the wake-up control information signal, determines that UE1 is about to transmit sidelink data, wakes up, monitors the sidelink on duration (e.g., sidelink on durations 1, 2, and 3 in FIG. 2) until the time corresponding to the next wake-up control resource (e.g., at W2 in FIG. 2), as shown at 320, and receives the sidelink data transmitted by UE1 (as shown at 318). Conversely, if there is no sidelink data that needs to be transmitted by UE1 or the sidelink data buffer at UE1 is empty, UE1 will not transmit any wake-up control information or signaling (e.g., at W1). UE2 will monitor the wake-up control resources (at W1) but will not detect any wake-up control information or signaling and therefore will not wake up to monitor the sidelink resources (sidelink on durations 1, 2, and 3 in Fig. 2) for sidelink data communication.

In this example, referring to FIG. 2, UE1 may not use all of sidelink on durations 1, 2, and 3 to transmit sidelink data (e.g., UE1 may transmit data using only sidelink on duration 1), but UE2 will monitor all of sidelink on durations 1, 2, and 3 after receiving a wake-up control information or signal in W1 until it decides in W2 whether to monitor sidelink on durations 4, 5, 6, 7, and 8 during the next time division (between W2 and W3), depending on whether the sidelink control information or signal in W2 indicates a need for such monitoring. Alternatively, UE1 may be configured to transmit for only one sidelink on duration after transmitting a wake-up control information or signal. Thus, UE2 may need to monitor for only one sidelink on duration after each time it receives a wake-up control information or signal.

The wake-up control information or signal described above with respect to this embodiment may be, for example, a single-bit signal. For example, detection of such a signal implies the need to monitor one or more sidelink on durations during the next time division. Alternatively, the wake-up control information or signal may be transmitted within other forms of signals or messages.

Using the scheme described above, the receiving UE further reduced the power consumption for monitoring the sidelink resource pool by dividing the sidelink resource pool into multiple time divisions (or zones) as indicated using the time points corresponding to the wake-up control resources as defined in the wake-up control resource configuration. Thus, the receiving UE only needs to monitor one or more sidelink on durations within a time division after receiving the wake-up control information or signal, rather than monitoring the entire sidelink resource pool, thereby further reducing the power consumption for sidelink data monitoring.

The above wake-up control resource configuration may include at least one of the exemplary information items shown in the list below for defining and identifying resources allocated for transmitting/receiving wake-up control information or signals.
As shown in the exemplary List 2, the wake-up control resource configuration may include a sequence of resource configurations. Each configuration may include a time offset to define the time location (either time slot location or symbol location) of the corresponding wake-up control resource along the resource time axis of FIG. 2. The wake-up control configuration may further include an identifier for the wake-up resource configuration, for example, used to identify a frequency resource for each wake-up control resource configuration. In particular, the physical layer may allocate frequency resources for wake-up control information, or such frequency resources may be provided with an identifier by a higher layer, and such identifier may be included in the wake-up control configuration. Alternatively or in addition, a PSCCH resource ID information item may be included to identify the frequency allocation. A wake-up identifier may further be included, for example, to identify a sequence of wake-up control resource configurations. Optionally, but not shown in List 2 above, the wake-up control resource configuration may further include a source identification or a service destination identification to limit the availability of a particular wake-up control resource configuration.
Second Exemplary Embodiment

The various implementations of the second embodiment described below are similar to the implementations of the first embodiment above. The following description focuses on their differences. Other aspects of the second embodiment not explicitly included below under this heading can be found above in the description of the various implementations of the first embodiment.

For this second exemplary embodiment, it is also assumed that a first UE (UE1) and a second UE (UE2) have established a connection for sidelink communication, for example in unicast mode. UE1 represents a sidelink data transmitter and UE2 represents a corresponding sidelink data receiver. In this embodiment, the wake-up control information may be implemented as a sidelink control information (SCI) message, referred to as a power saving sidelink control information (PS-SCI) message. Instead of only a wake-up signal (such as a single bit indicator signal) for the wake-up control information in the first embodiment, the PS-SCI message may be used to carry additional information. The PS-SCI message, like other SCI information, may be carried, for example, by the PC5 interface.

An exemplary PS-SCI message may include at least one of the following items of information:
A wake-up indication (e.g. a 1-bit indicator/signal) to indicate to the receiving UE whether to monitor the sidelink on-duration or the sidelink resource pool for sidelink data following the time of receiving the PS-SCI message until the time for the next PS-SCI resource. Such an indicator provides a similar function to the wake-up control information in the first embodiment.
- Destination Identity (or Service Identity) to identify the service corresponding to the sidelink communication. Such information helps the receiving UE to determine the destination identity and the service type and therefore whether the service is noteworthy. If the service is not noteworthy, the receiving UE may refrain from monitoring subsequent sidelink on durations for sidelink data.
- Secondary Cell (SCell) dormancy indication information for multi-carrier scenarios. In particular, with such an indicator in a multi-carrier scenario, the recipient UE only needs to monitor for PS-SCI control resources on one of the carriers and obtain wake-up control information for the other carriers. Such an indicator may be provided as a carrier bitmap, where each bit of the bitmap corresponds to one of the SCell groups configured by higher layers of the radio network, with the most significant bit (MSB) to the least significant bit (LSB) of the bitmap corresponding to the first to last configured SCell group.

Corresponding to a PS-SCI message serving as wake-up control information, a wake-up control resource configuration may be defined to identify the control resources required for transmitting/receiving the PS-SCI message. Such a resource configuration is referred to as a PS-SCI resource configuration (corresponding to the wake-up control resource configuration described in the first embodiment). PS-SCI resource allocation for sidelink communication may be defined as a PS-SCI resource configuration, each of which may include at least one of the information items shown in List 3 below.

As shown in exemplary Listing 3, a PS-SCI resource configuration may include a sequence of PS-SCI control configurations, each corresponding to one of W1-W6 in Figure 2. An exemplary PS-SCI resource configuration may include a time offset to define the time location of the corresponding PS-SCI resource for carrying a PS-SCI message (which serves as wake-up control information). Other information items that may be included in a PS-SCI resource configuration are shown and described in more detail below in Listing 4.

For example, a wake-up configuration indicator may optionally be included in the PS-SCI configuration, indicated by slps-WakeUp in List 4 above. Whether the recipient UE wakes up to monitor the subsequent sidelink on duration or the sidelink resource pool is determined according to the wake-up indication information or signal in the received PS-SCI message, but the wake-up configuration indicator in the PS-SCI configuration may be designed to indicate to the UE whether to monitor the subsequent sidelink on duration or the sidelink resource pool when a PS-SCI message is not received at a certain time for the corresponding resource allocated to the PS-SCI message. Specifically, when the wake-up configuration indicator is included in the PS-SCI configuration, the UE is required to monitor for sidelink data when a PS-SCI message is not received, otherwise, when the wake-up configuration indicator is not included in the PS-SCI configuration, the UE is not required to monitor for sidelink data. Alternatively, when the wake-up configuration indicator is not included in the PS-SCI configuration, the UE is required to monitor for sidelink data when no PS-SCI message is received, and otherwise, when the wake-up configuration indicator is included in the PS-SCI configuration, the UE is not required to monitor for sidelink data. Such a configuration scheme would allow an optional configuration parameter to make the UE monitor for sidelink data when a transmitted PS-SCI message is not received, so that sidelink data can still be received even if a corresponding PS-SCI message was transmitted but lost during its transmission.

For this second embodiment, FIG. 4 illustrates an exemplary logic flow 400 for information exchange between UE1 and UE2. Exemplary logic flow 400 is similar to logic flow 300 of FIG. 3 for the first embodiment, except that wake-up control resource configuration and wake-up control information or signaling are replaced by PS-SCI resource configuration and PS-SCI messages, respectively. Details of steps 406, 408, and 410 can be found above, e.g., in the description of steps 306, 308, and 310, respectively, and will not be repeated here.

In FIG. 4, UE2 monitors PS-SCI resources (e.g., W1-W6 in FIG. 2) for PS-SCI messages. Once a PS-SCI message is detected, UE2 determines the wake-up indicator contained therein and decides whether to monitor the subsequent sidelink on duration or sidelink resource pool until the next time point corresponding to the next PS-SCI resource (next W in FIG. 2). Specifically, the UE proceeds to monitor the subsequent sidelink on duration or sidelink resource pool for sidelink data when indicated by the wake-up indicator, and does not monitor otherwise. In addition to FIG. 4, whether UE2 is required to monitor the sidelink on duration or sidelink pool when a PS-SCI message is not received at a time point (e.g., W1-W6 in FIG. 2) configured as a PS-SCI resource is determined by the wake-up configuration indicator (e.g., slps-WakeUp indicator in List 4) described above.

In both the first and second embodiments, the wake-up control information/signal or PS-SCI message is transmitted by UE1 only when there is subsequent sidelink data to transmit. The wake-up control information/signal or PS-SCI message is not transmitted otherwise. In addition, the UE is configured to constantly monitor the wake-up control or PS-SCI resources that are allocated and configured by the wake-up control or PS-SCI resource configuration (e.g. W1-W6 resources in FIG. 2).
Third Exemplary Embodiment

The various implementations below for the third exemplary embodiment focus on sidelink control resource configuration for groupcast sidelink communication. It is assumed that a first UE (UE1) and a second UE (UE2) have established a connection for sidelink communication in groupcast mode. UE1 represents a sidelink data transmitter and UE2 represents a corresponding sidelink data receiver. UE1 and UE2 are in a group of UEs forming a groupcast UE group, alternatively referred to as a sidelink communication group. The sidelink communication group may further include a representative UE (referred to as a group representative), which is denoted as UE3. The implementations below are designed to enable UEs in a sidelink communication group to reduce their power consumption when monitoring and receiving groupcast sidelink data.

In some implementations, if UE2 has power saving requirements (e.g., UE2 is a P-UE), after UE2 joins the sidelink communication group, UE3 (representative UE) is informed by NAS layer signaling that there is at least one P-UE in the sidelink communication group and that power saving policies/configurations need to be initiated. For example, a sidelink resource pool or sidelink DRX as shown in FIG. 2 with limited sidelink on duration may be allocated and configured for sidelink data communication for UEs (such as UE2) in the sidelink communication group.

In some implementations of this embodiment, similar to the above implementations in the first embodiment, the time range that the UE2 is required to monitor for sidelink data may be divided into several time divisions and a corresponding sidelink wakeup control resource may be configured at the start of each time division. Sidelink wakeup control information or signaling may be carried via the sidelink wakeup control resource to indicate to the UE2 whether the UE2 is required to monitor the sidelink on duration after a first time point corresponding to a sidelink wakeup control resource until a second time point corresponding to a next time point associated with the next wakeup control resource.

FIG. 5 shows a logic flow 500 illustrating the sidelink control configuration of UE1 and UE2 and the information exchange between UE1 (502), UE2 (504), and representative UE3 (505) for sidelink data communication from UE1 to UE2. As shown in FIG. 5, transmitting UE1 502, receiving UE2 504, and representative UE3 505 may establish a sidelink connection in step 506. The UE group members may further exchange sidelink capabilities as shown at 508 and described above. Such a capability exchange would, for example, inform UE3 that UE2 has power saving requirements (e.g., UE2 is a P-UE).

Regarding power saving using sidelink time division, a wake-up control resource configuration for the sidelink communication group may be transmitted from UE3 to UE1 and UE2 (and other members of the group not shown in FIG. 5) as shown by 510 and 511 in FIG. 5. The wake-up control resource configuration may be transmitted, for example, via the PC5-RRC channel and interface. The wake-up control resource configuration may be provided by the network side. For example, the network side of UE3 (e.g., the WANN of its serving cell) may provide such a wake-up control resource configuration, and UE3 may obtain the wake-up control resource configuration from the network side and then transmit the wake-up control resource configuration to the members of the sidelink control group (such as UE1 and UE2). In order for UE3 to obtain such a configuration from its network side, UE3 may transmit a request containing sidelink UE information to its network side. Such sidelink UE information may, for example, include at least one of the various items in list 1 above. Such UE information may further optionally include information of group members in the sidelink control group, such as group member identifiers and the number of group members. In some other implementations, the wake-up control resource configuration may be obtained from the network side by the group members, rather than from the representative UE.

The wake-up control resource configuration for the sidelink communication group may include at least one of the exemplary information items shown in List 2 above. For example, the wake-up control resource configuration may include a sequence of resource configurations. Each configuration may include a time offset to define the time location (either time slot location or symbol location) of the corresponding wake-up control resource along the resource time axis of FIG. 2. The wake-up control resource configuration may further include an identifier for the wake-up resource configuration, for example, used to identify a frequency resource for each wake-up control resource configuration. In particular, the physical layer may allocate frequency resources for the wake-up control information, or such frequency resources may be provided with an identifier by a higher layer, and such identifier may be included in the wake-up control configuration. Alternatively or in addition, a PSCCH resource ID information item may be included to identify the frequency allocation. A wake-up identifier may also be included, for example, to identify a sequence of wake-up control resource configurations. Optionally, although not shown in List 2 above, the wake-up control resource configuration may further include a source identification or a service destination identification to limit the availability of a particular wake-up control resource configuration.

Continuing with reference to FIG. 5, member UEs in the group, such as UE2 and UE1, receive a wake-up control resource configuration from UE3, as indicated by 510 and 511. In step 512, when UE1 has a sidelink to transmit or its sidelink data buffer is not empty, it first transmits a wake-up control information or signal on a wake-up control resource (e.g., sidelink control time resource W1 in FIG. 2) preceding the sidelink resource, as indicated by 514, to transmit sidelink data (resource bar or sidelink on duration 1 in FIG. 2) to UE2 via the sidelink control channel (PSCCH), as indicated by 514, which is monitored by UE2. UE2 receives the wake-up control information signal, determines that UE1 is about to transmit groupcast sidelink data, wakes up, monitors the sidelink on duration, as indicated by 520, until the time corresponding to the next wake-up control resource, and receives the sidelink data transmitted by UE1 (as indicated by 518). Conversely, if there is no groupcast sidelink data that needs to be transmitted by UE1 or the sidelink data buffer at UE1 is empty, UE1 will not transmit any wake-up control information or signaling. UE2 will monitor the wake-up control resources but will not detect any wake-up control information or signaling and therefore will not wake up to monitor the sidelink resources for sidelink data communication.

The content of the wake-up control information or signal is similar to that of the first embodiment described above.

In groupcast sidelink applications, member UEs in a sidelink communication group may share the same wake-up control resources, as defined in the wake-up control resource configuration above. Under such wake-up resource sharing, after a UE transmits wake-up control information or signaling and proceeds to transmit sidelink data, it may not be able to simultaneously monitor the wake-up control resources for wake-up control information or signaling. In some implementations, to avoid data reception loss, a transmitting UE may be configured to always monitor for sidelink data during the sidelink on duration or sidelink resource pool in the next time division after transmitting wake-up control information and sidelink data during the previous time division.

Alternatively, member UEs of a sidelink communication group may be configured with separate wake-up control resources rather than shared wake-up control resources. For example, the group representative UE 3 may configure different wake-up control resources for each UE in the group. Thus, each wake-up control resource configuration in the sequence of wake-up control resource configurations of List 2 may be adapted to include a group member ID indicating the group member of the sidelink communication group to which the particular wake-up control resource configuration is applicable. An exemplary modified sequence of wake-up control resource configurations is shown in List 5 below.

The group wake-up control resource configurations of List 5 each include a sequence of wake-up control resource configurations for one of the members of the group. Each wake-up control resource configuration may include a set of time offsets to define the time slot or symbol location of one or more wake-up control resources. The information item "wakeUpResearchId" or "PSCCH-ResourceId" is related to the identification of the frequency resource allocated to carry the wake-up control information or signal and is the same as the corresponding information item in List 2, which is described in more detail in connection with the first embodiment. Each wake-up control resource configuration of List 5 specifically includes an identifier for the corresponding group member ("GroupMember ID") to indicate the member UE to which a particular wake-up control resource in the wake-up control resource configuration is allocated.

In some other implementations, especially when the number of group members is large and it becomes impractical to provide each group member with a distinct wake-up control resource configuration, a set of wake-up control resource configurations may be allocated and one or more of the wake-up control resource configurations may be shared by more than one group member. For these implementations, the "GroupMemberID" in Listing 5 for a particular wake-up control resource configuration above may include a set of IDs (rather than a single group member ID) for the group members sharing this particular wake-up control resource allocation. Alternatively, a group member bitmap may instead be implemented to indicate the group members sharing this particular wake-up control resource allocation (e.g., with 0 and 1 bits corresponding to members in the bitmap that share this particular resource and members that do not, respectively). Group members that share wake-up control resources with others may be configured to monitor for sidelink data during the sidelink on duration or sidelink resource pool in the next time division at all times after transmitting sidelink data during the previous time division. Group members that do not share wake-up control resources with others may not need to monitor for sidelink data during the sidelink on duration or sidelink resource pool in the next time division after transmitting sidelink data during the previous time division. Therefore, the wake-up control resource configuration may optionally include an indicator that indicates whether the UE should monitor the sidelink on duration or sidelink resource pool during the next time division after transmitting wake-up control information or signaling.

Other aspects not explicitly described with respect to the third embodiment may be found in the description of the first embodiment.
Fourth embodiment

Various implementations of the fourth embodiment relating to groupcast sidelinks described below are similar to the implementations of the third embodiment above in combination with the second embodiment. Other aspects of this fourth embodiment not explicitly included below under this heading can be found above in the description of various implementations of the third and second embodiments.

As in the third embodiment, for this fourth exemplary embodiment, it is assumed that a first UE (UE1) and a second UE (UE2) have established a connection for sidelink communication in groupcast mode. UE1 represents a sidelink data transmitter and UE2 represents a corresponding sidelink data receiver. UE1 and UE2 are in a group of UEs forming a groupcast UE group, alternatively referred to as a sidelink communication group. The sidelink communication group may further include a representative UE (referred to as a group representative), denoted UE3. The implementation below is designed to enable UEs in a sidelink communication group to reduce their power consumption when monitoring and receiving groupcast sidelink data.

Various aspects of this fourth embodiment are similar to the third embodiment, with the wake-up control information being replaced by the PS-SCI message described in the second embodiment. The content of the PS-SCI message is similar to that described above in the second embodiment. Furthermore, the wake-up control resource configuration of the third embodiment is replaced with a PS-SCI resource configuration, which may be implemented in a manner similar to that of the second embodiment.

Figure 6 shows a logic flow 600 illustrating the sidelink control configuration of UE1 and UE2 and the information exchange between UE1 (602), UE2 (604), and representative UE3 (605) for sidelink data communication from UE1 to UE2. Exemplary logic flow 600 is similar to logic flow 500 of Figure 5 for the third embodiment, where again the wake-up control resource configuration and wake-up control information or signal are replaced by PS-SCI resource configuration and PS-SCI messages, respectively. Details of steps 606, 608, 610, and 611 can be found above, e.g., in the description of steps 506, 508, 510, and 511, respectively, and are not repeated here.

The PS-SCI resource configuration may include a sequence of PS-SCI control configurations similar to those specified in List 4 and described above with respect to the second embodiment, which are not duplicated here.

PS-SCI resource sharing among group member UEs may be similarly implemented as described above with respect to the third embodiment. For example, members of a sidelink communication group may each be configured with separate PS-SCI resources. Alternatively, one or more of the members may share PS-SCI resources. Such sharing may be indicated by an additional information item of the PS-SCI resource configuration indicating the sharing group members of a particular PS-SCI resource. In such an implementation, a UE sharing PS-SCI resources with other UEs of the group may be configured to always monitor for sidelink data during a sidelink on duration or sidelink resource pool in the next time division after transmitting a PS-SCI message and sidelink data during a previous time division. Group members that do not share PS-SCI resources with others may not need to monitor for sidelink data during a sidelink on duration or sidelink resource pool in the next time division after transmitting a PS-SCI message and sidelink data during a previous time division. Thus, the PS-SCI resource configuration may optionally include an indicator indicating whether the UE should monitor the sidelink on duration or the sidelink resource pool during the next time division after transmitting the PS-SCI message and the sidelink data. These optional information items that may be included in the PS-SCI resource configuration are similar to the corresponding optional information items described above in the third embodiment regarding the wake-up control resource configuration.

Other aspects not explicitly described with respect to the fourth embodiment may be found in the descriptions of the third and second embodiments.
Fifth embodiment

The embodiments provide various exemplary implementations for configuring sidelink resources. In this embodiment, the sidelink resource configuration may be pre-configured for the UE or may be obtained by the UE from the network side (e.g., the WANN of its serving cell). This resource configuration combines the configuration of both sidelink resources for data transmission and sidelink control resources for power saving. The sidelink control resources may include wake-up control resources or PS-SCI resources, as described above in the first and third embodiments.

For example, the sidelink resource configuration may include a sidelink resource pool such as that shown in FIG. 2. The sidelink resource configuration may further include a wake-up control resource configuration indicating one or more wake-up control resources for transmitting wake-up control information or signals. The sidelink resource configuration may optionally include a power saving indicator to indicate that the sidelink resource pool included in the sidelink resource configuration may be used by a power saving UE (such as a P-UE).

Such a sidelink resource configuration may be used, for example, within a sidelink broadcast. The receiving UE may be pre-configured with such a sidelink resource configuration or may obtain such a sidelink resource configuration from its network side. The receiving UE may be configured to constantly monitor the wake-up control resource for wake-up control information or signals. When the receiving UE detects the wake-up control information or signal, it then wakes up and monitors the sidelink resource pool to receive sidelink data until the time corresponding to the next wake-up control resource. If the receiving UE does not detect any wake-up control information or signal, it does not need to wake up and monitor the sidelink resource pool for sidelink data. With reference to FIG. 2, for example, if the receiving UE receives a wake-up control information or signal at time W1 indicating that the receiving UE needs to wake up and monitor for sidelink data, it wakes up and monitors the sidelink resource pool (sidelink resources 1, 2, and 3) after W1 but before W2 to monitor and receive sidelink data. For another embodiment, if the receiving UE monitors the wake-up control resources in W2 and does not receive any wake-up control information or signal, the receiving UE does not need to wake up after W2 and before W3 and monitor the sidelink resource pool (e.g., sidelink-resources 4, 5, 6, 7, and 8) to receive sidelink data.

The transmitting UE may also be pre-configured with such a sidelink resource configuration or obtain such a sidelink resource configuration from its network side. When the transmitting UE determines that there is sidelink data to transmit (e.g., for broadcast), it first transmits wake-up control information or signals on the wake-up control resources indicated in the wake-up control resource configuration. For example, the transmitting UE may use the next available wake-up control resource (in time) following the determination of the need to transmit data. The transmitting UE then transmits the sidelink data using the sidelink resource pool between the time corresponding to the wake-up resource it used to transmit the wake-up control information/signal and the time corresponding to the wake-up resource it used to transmit the next wake-up control resource. In other words, the transmitting UE always transmits wake-up control information or signals on the wake-up control resources before transmitting sidelink data on the sidelink resource pool. With reference to Figure 2, for example, if a transmitting UE determines that it has sidelink data to transmit just before W1, it may first transmit sidelink control information or signaling in W1 and then, if necessary, transmit the sidelink data via sidelink resources (1, 2, and 3). If the transmitting UE needs more sidelink resources than resources 1, 2, and 3 to transmit sidelink data, it may further transmit another wake-up control information or signaling in W2 and continue to use one or more of sidelink resources 4, 5, 6, 7, and 8 for transmitting the additional sidelink data.
Sixth embodiment

This embodiment provides various example implementations for configuring a sidelink resource pool for power saving in sidelink communications.

One or more resource pools may be configured for the sidelink. Some of these sidelink resource pools may be associated with power saving usage. Such power saving sidelink resource pools may, for example, comprise a small time resource range compensated by a large frequency resource range, such that a power saving UE only needs to monitor such a sidelink resource pool for sidelink data for a short duration.

In some implementations, one or more power-saving sidelink resource pools may be further divided into sidelink resource time divisions. Each sidelink time division may be a portion of a sidelink resource pool, one sidelink resource pool, or multiple sidelink resource pools. For example, one or more power-saving sidelink resource pools may be divided into N sidelink resource time divisions. In some implementations, the number N may be explicitly or implicitly indicated in one or more sidelink resource configurations corresponding to one or more power-saving sidelink resource pools. The manner in which the time division of one or more power-saving sidelink resource pools is performed is described in various example implementations below.

These sidelink resource time divisions may be selected by the UE for sidelink communication based on the traffic type. Such traffic types may include, but are not limited to, the service destination identity, the cast type (broadcast, groupcast, or unicast), and the QOS type (e.g., represented by a QFI or a QoS profile). For example, if a power saving UE is interested in a sidelink broadcast service corresponding to a certain type of traffic, it may monitor the sidelink resource time division corresponding to that traffic type. For example, such sidelink resource time divisions may be used by the UE based on the destination identity of the sidelink communication. Just as an example implementation, for a sidelink broadcast service destination identity = x, the broadcasting UE may select the yth sidelink resource time division from the N time divisions according to y = MOD(X,N). For another example, assuming m = log ₂ N, the broadcasting UE may select the yth sidelink resource time division from the N time divisions according to y, which is the value of the m most significant bit (MSB) or m least significant bit (LSB) of the service destination identity. Other manners of mapping the destination identity to the N time divisions of one or more sidelink resource pools are also possible.

UEs that are within the coverage range of a serving cell may be configured by the WAN for the sidelink resource configuration. UEs that are not covered by the serving cell may be pre-configured. Multiple sidelink resource pools may be configured. Each sidelink resource pool may correspond to one sidelink resource configuration. For a particular sidelink resource pool, the corresponding sidelink resource configuration may include a power saving indicator to indicate whether the sidelink resource pool is designated for power saving use (in some implementations, the absence of such an indicator indicates that the resource pool is designated for normal use rather than power saving use). The sidelink resource configuration may further optionally include a numeric value N to indicate the number of resource time divisions of one or the aggregate power saving sidelink resource pools. The sidelink resource configuration may further optionally include a traffic type indicator, such as a service destination indicator, to indicate whether the sidelink resource pool allocated in this configuration is to be used by the UE based on the traffic type of the sidelink communication. Various example implementations of sidelink resource configuration are illustrated in Figs. 7-9 and described in more detail below.

As shown in Fig. 7, a particular sidelink resource pool 702 may be configured for sidelink communication. The corresponding sidelink resource configuration may, for example, include a resource bitmap 704 to indicate the sidelink resources contained in the sidelink resource pool 702. The sidelink resource configuration may include a positive number N to indicate the number of sidelink source time divisions of the sidelink resource pool 702, as indicated by 706. In some implementations, the sidelink resources may be partitioned in time in an interlaced manner. As shown by Fig. 7, merely as an example, the sequence of time resources of the sidelink resource pool is indicated by 1, 2, ..., 10. These time resources are partitioned into N=5 time divisions, containing time resources (1, 6), (2, 7), (3, 8), (4, 9), and (5, 10). Other rules of partitioning are also conceivable. Such rules of partitioning may be predefined. The sidelink resource configuration may further include a power saving indicator to indicate that the sidelink resource pool 702 is available for use by a power saving UE. Alternatively, the presence of a positive number N in the sidelink resource configuration may be used as such an indicator. The sidelink resource configuration may further optionally include a traffic type indicator to indicate the type of traffic for which the sidelink resource pool 702 may be used by the UE, including, but not limited to, a service destination identification, a cast type, and a QOS type, as described above.

In some other implementations, as shown in FIG. 7, a particular sidelink resource pool 802 may be configured for sidelink communications. The corresponding sidelink resource configuration may, for example, include N separate resource bitmaps 804, 806, ..., and 808 to indicate the time division of the sidelink resources in the sidelink resource pool 802. The sidelink resource configuration may optionally include a positive number N to indicate the number of time divisions of the sidelink resources. Alternatively, the positive number N may not be explicitly included in the configuration, since it may be implicitly derived from the number of bitmaps 804, 806, ..., and 808. The sidelink resource configuration may further include a power saving indicator to indicate that the sidelink resource pool 702 is usable by power saving UEs. Alternatively, the presence of the positive number N or the presence of multiple bitmaps 804, 806, ..., and 808 may be used as an indication that the sidelink resource pool 802 may be used for power saving. The sidelink resource configuration may further optionally include a traffic type indicator to indicate the type of traffic that the sidelink resource pool 702 may be used for by the UE, including, but not limited to, a service destination identification, a cast type, and a QOS type, as described above.

In some other implementations, N sidelink resource pools may be configured to collectively form N time divisions. FIG. 9 shows sidelink resource pools 902, 904, 906, and 908 forming N time divisions for power saving use. Each sidelink resource pool serves as one sidelink resource time division. Each of these pools is associated with a sidelink resource configuration. Each sidelink resource configuration may include a resource bitmap, as shown by 912, 914, 916, and 918. The collection of sidelink resource pools 902, 904, 906, and 908 may be selected for use by a power saving UE. The sidelink resource configuration for each of the sidelink resource pools, e.g., sidelink resource pool 902, may optionally include a positive numeric value N to indicate the number of pools (or time divisions) involved in power saving use. The sidelink resource configuration may further include a power saving indicator to indicate that the sidelink resource pool 702 is usable by a power saving UE and to indicate that the sidelink resource pool corresponding to the sidelink resource configuration is part of a set of resource pools forming N time divisions. The sidelink resource configuration may further optionally include a traffic type indicator to indicate the type of traffic for which the sidelink resource pool 702 may be used by the UE, including, but not limited to, a service destination identification, a cast type, and a QOS type, as described above. Thus, the power saving sidelink resource pools 902, 904, 906, and 908 may be configured as either traffic type specific or of general use for power saving sidelink communications.

With the various sidelink resource configurations and allocations of the resource pools described above, a transmitting (e.g., broadcasting) UE may perform the following steps when transmitting sidelink data. The transmitting UE may first receive the sidelink resource configuration either by pre-configuration or from its network side (e.g., its serving cell's WANN). When the transmitting UE needs to transmit sidelink data, it selects a time division from the sidelink resources according to the traffic type of the sidelink communication. For example, the transmitting UE may select one or more of the N time divisions of the sidelink resources for transmission based on the destination identification of the sidelink communication.

Similarly, a receiving UE of broadcast sidelink data may perform the following steps when receiving sidelink data. The receiving UE may first receive a sidelink resource configuration either by pre-configuration or from its network side (e.g., the WANN of its serving cell). The receiving step then monitors the sidelink resource of interest. For example, if the receiving UE is interested in a broadcast data service with a particular destination identity, it selects a corresponding time-division of the sidelink resource and monitors it for sidelink data. The sidelink data corresponding to the destination identity of interest will be transmitted within the time-division of the sidelink resource monitored by the receiving UE according to the various schemes and implementations of resource allocation and configuration described above.

In some implementations, when a UE receives a sidelink resource allocation from its serving WANN, the UE may obtain a sidelink resource configuration using the following example procedure: The UE may first send a Buffer Status Report (BSR) to the WANN to request a sidelink resource allocation. The BSR may include (e.g., as an index) traffic type information (such as a service destination identification), a logical channel group (LCG) identifier, and a buffer size. The WANN may allocate sidelink resources according to these parameters in the BSR and transmit one or more sidelink resource configurations to the UE. The sidelink resource configuration may include an allocation of sidelink resources and a traffic type index. The UE may then transmit data of a traffic type (e.g., a service destination) via the sidelink resources according to the various implementations described above.
Seventh embodiment

Various implementations for this embodiment combine the implementations of the fifth and sixth embodiments above for sidelink resource configuration embedded with additional wake-up control resource configuration to further reduce UE power consumption in sidelink communications.

For example, the wake-up control resource configuration described above in the fifth embodiment may be embedded within the various sidelink resource configurations described in the sixth embodiment. The wake-up control resource configuration indicates one or more wake-up control resources for transmitting wake-up control information or signals. The wake-up control information or signals may be transmitted by the UE prior to a sidelink data transmission and indicate to the receiving UE to monitor the sidelink resources for sidelink data after a first time point corresponding to the wake-up control resource used to transmit the wake-up control information and a second time point corresponding to the next wake-up control resource defined in the wake-up control configuration.

Each sidelink resource pool may be associated with a sidelink resource configuration. Each sidelink resource configuration may include one or more wake-up control resource configurations. Each wake-up control resource configuration may include one or more wake-up control resources.

According to such sidelink resource configuration, when a transmitting UE determines that there is sidelink data to transmit (e.g., for broadcast), it first transmits wake-up control information or signals on the wake-up control resources indicated in the wake-up control resource configuration. For example, the transmitting UE may use the next available wake-up control resource following the determination of the need to transmit data. The transmitting UE then transmits the sidelink data using the sidelink resource pool between the time corresponding to the wake-up resource it used to transmit the wake-up control information/signal and the time corresponding to the wake-up resource it used to transmit the next wake-up control resource. In other words, the transmitting UE always transmits wake-up control information or signals on the wake-up control resources before transmitting sidelink data on the sidelink resource pool. The selection of sidelink resources for transmitting sidelink data may be based on various implementations described in the sixth embodiment. For example, the UE may use sidelink resources in a time division selected based on the traffic type of the sidelink communication.

The receiving UE may be configured to constantly monitor the wake-up control resources for wake-up control information or signals. When the receiving UE detects the wake-up control information or signal, it then wakes up and monitors the sidelink resource pool to receive sidelink data until the time corresponding to the next wake-up control resource. If the receiving UE does not detect any wake-up control information or signal, it does not need to wake up and monitor the sidelink resource pool for sidelink data. The selection of the sidelink resources for monitoring the sidelink data may be based on various implementations described in the sixth embodiment. For example, the receiving UE may use sidelink resources within a time division that are selected based on the traffic type of the sidelink communication (e.g. a destination identity corresponding to a sidelink broadcast service that is of interest to the receiving UE).
Eighth embodiment

This embodiment provides an exemplary implementation for establishing a unicast sidelink connection between UEs in a power saving manner.

For example, if UE1 has not established any sidelink connection with UE2 for unicast sidelink communication, it cannot communicate with UE2 according to the power saving scheme described in the previous embodiment. During this time, UE2 may monitor messages broadcast by UE1. For example, UE2 may monitor a Direct Communication Request (DCR) message from UE1. Since the DCR message is carried within a broadcast signal, the scheme in the above embodiment for broadcast sidelink communication may be used for power saving. Specifically, since UE1 sends the DCR message via PC5 broadcast using source layer-2 ID and destination layer-2 ID, the monitoring of the broadcast data may be based on the fifth, sixth, and seventh embodiments above. In addition, since the DCR message also includes other information, including, but not limited to, optional information of the target user information (e.g., if the broadcasting UE can determine the target user information of the receiving UE, it can optionally include the target user information, otherwise it does not include the target user information), if the broadcast message carries the target user information of the recipient UE2, it can use the target user information as a destination identity for calculating the time location of the resource pool for transmission, and thereby determining the time location for transmitting the wake-up control information. The recipient UE2 may correspondingly use its application layer ID as a destination identity for calculating the time location of the resources for receiving the broadcast data. If the broadcast message does not carry the target user information of the recipient UE2, other information such as the initial application layer ID or V2X service information may be used as a destination identity for UE1 to calculate the time location of the resources for the transmission of the wake-up control information and the broadcast message. Correspondingly, with regard to UE2, if it has an interest in this type of unicast service, it can use these parameters to calculate the time location of the resources.
Ninth embodiment

This embodiment provides an exemplary implementation for establishing a groupcast sidelink connection between UEs in a power saving manner.

For example, a P-UE may have an interest in a service associated with a groupcast. The P-UE may not yet be a group member and may not have established any PC5 RRC group connection with a UE in the group. If all UEs in the group support the power saving sidelink feature, the sidelink resource pool for the P-UE may be time-divided according to traffic type, such as service destination identity (as described above in the sixth embodiment). For example, the power saving resource pool may be divided into N time divisions. For a groupcast data transmission with a destination identity of x, a time division index y may be selected, for example, according to y=mod(x, N). For another example, assuming m=log2N, y is the value of the m most significant bits (MSBs) or m least significant bits (LSBs) of the service destination identity. Correspondingly, wake-up or PS SCI control resources can be further configured per resource pool. Then, if a UE needs to send a groupcast message, it first transmits wake-up or PS-SCI information or signal before sending the groupcast message. For UEs covered by the serving cell, the power saving sidelink resources can be configured by the WAN. For example, when configuring a resource pool for a P-UE, an indicator may be included in the configuration to indicate whether the resource pool supports power saving functionality. A number N may be optionally included. A traffic type indicator may also be included to indicate whether the resource pool may be used based on traffic type. A wake-up or PS-SCI resource configuration may also be included for each resource pool, indicating the wake-up or PS-SCI resources.

Furthermore, as described in the second embodiment, if the PS-SCI method is used, the PS-SCI message can also carry a traffic type, such as a service destination identity, which is used to indicate the service/traffic that will be transmitted in the next sidelink resource. UEs that have an interest in this type of service or traffic type will then wake up and monitor the sidelink resources for sidelink data. The UE further calculates a time division index y according to the traffic type, such as a destination identity. Different y may correspond to different PS-SCIs, thereby further reducing the amount of wake-ups. If a wake-up signal is used instead, the wake-up control resource can be determined by calculating y based on the traffic type, such as a destination identity, thereby reducing the amount of wake-ups.

If different wake-up or PS-SCI resources are configured in different serving cells, the transmitting and receiving UEs may misinterpret each other. Such configuration may require coordination between the serving cells. Such coordination may involve the OAM (operation, administration, and maintenance) functions of the wireless network.

If the P-UE also needs to receive data from a legacy sidelink UE (a UE that does not support power saving features) that does not send a wake-up control signal, the P-UE may miss monitoring the sidelink data (since it does not receive any wake-up control signal). To avoid this, the transmission and reception resources of the legacy UE and the P-UE may be separated. The transmission resources of the legacy UE and the reception resources of the P-UE may be configured separately.

Throughout this specification and the claims, terms may have subtle meanings that are suggested or implied in the context beyond the explicitly stated meaning. Similarly, the phrase "in one embodiment/implementation" as used herein does not necessarily refer to the same embodiment, and the phrase "in another embodiment/implementation" as used herein does not necessarily refer to a different embodiment. For example, it is intended that the claimed subject matter includes combinations of the example embodiments, whether in whole or in part.

In general, terminology may be understood, at least in part, from usage in context. For example, terms such as "and," "or," or "and/or" as used herein may include various meanings that may depend, at least in part, on the context in which such terms are used. Typically, when used to relate a list such as A, B, or C, "or" is intended to mean A, B, and C, as used herein in an inclusive sense, as well as A, B, or C, as used herein in an exclusive sense. In addition, the term "one or more" as used herein may be used to describe any feature, structure, or characteristic in a single sense, or may be used to describe a combination of features, structures, or characteristics in a multiple sense, depending at least in part on the context. Similarly, terms such as "a," "an," or "the" may be understood to convey a single usage, or to convey a multiple usage, depending at least in part on the context. In addition, the term "based on" may be understood as not necessarily intended to convey an exclusive set of factors, and instead may allow for the existence of additional factors not necessarily explicitly described, again depending at least in part on the context.

References to features, advantages, or similar language throughout this specification do not imply that all of the features and advantages that may be realized using the solution should or are included in any single implementation thereof. Rather, language referring to features and advantages is understood to mean that the specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the solution. Thus, discussions of features and advantages and similar language throughout this specification may, but do not necessarily, refer to the same embodiment.

Furthermore, the described features, advantages, and characteristics of the solution may be combined in any suitable manner in one or more embodiments. Those skilled in the art will recognize, in light of the description herein, that the solution may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in an embodiment that may not be present in all embodiments of the solution.

Claims (8)

1. A method for wireless sidelink communications, the method comprising:
receiving, by a UE, a radio resource configuration for a sidelink resource pool, the sidelink resource pool being divided into N time divisions, the radio resource configuration including a power saving indicator for indicating that a corresponding sidelink resource pool is usable by the UE for sidelink communications in a power saving mode;
and selecting, by the UE, for sidelink communication from the N time divisions of the sidelink resource pool based on a traffic type of the sidelink communication,
wherein N is a positive integer, and the traffic type is indicated by at least one of a destination identification, a cast type, or QoS information of the sidelink communication, the QoS information including at least one of a QoS flow identification and a QoS profile corresponding to the sidelink communication. The radio resource configuration comprises:
a first information element for identifying sidelink resources allocated to the radio resource configuration;
and a second information element comprising a positive integer equal to N. The radio resource configuration comprises:
a first information element including an N-time bitmap for identifying the N -time divisions of the sidelink resource pool;
and a second information element for indicating frequency allocation information for all N time divisions of the sidelink resource pool. The or each of the plurality of radio resource configurations comprises:
a radio resource configuration identifier , or
The method of claim 1 , further comprising at least one of: a traffic type indicator for indicating one or more traffic types. The method of claim 1, wherein the or each of the plurality of radio resource configurations comprises one or more sidelink control resource configurations for indicating a set of sidelink control resources for transmitting one or more sidelink control information. The method of claim 5, wherein each sidelink resource pool comprises one or more sidelink on durations. The method of claim 5, wherein each of the one or more sidelink control resource configurations corresponds to one or more time points corresponding to the one or more sidelink control information. the sidelink control information is transmitted at one or more time points;
The method of claim 7 , wherein the configured time period corresponds to a time between the point in time and a next point in time at the one or more points in time.